Making a modern automatic pistol from scratch in a home workshop. Is it possible?

Could someone with a middle class income acquire the shop tools to make a modern automatic pistol like the Glock or similar entirely from scratch? And by scratch I mean starting with billets of metal and crafting every single part of the gun except for springs, bolts and screws etc which they could buy from supply houses. Let's assume this person could have accumulated up to 100K worth of various work shop tools and equipment over the course of 10 years to accomplish this.

Is this possible or are there some machining requirements simply beyond the scope of home workshop manufacture?

It's certainly possible to make something that would work once starting from scratch, even if you had to machine your own parts. Manufacturers sometimes sell blanks (unmachined cast metal parts) so you could use those as well. If you're buying springs and little fiddly bits, I think it's possible, but it'd be a lot of work for something that might or might not work. I assume you're not extruding your own barrels? Even then they'd need to be rifled and pressure tested, likewise the breech parts and ejector. Automatics are complicated machines -- a revolver would be much easier. So put me down for the "possible but a lot of trouble"crowd, someone more experienced will probably be in shortly.

(And I'm having flashbacks to Line of Fire, when John Malkovich made a plastic 2 shot pistol at home.)

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- - - Well, yes, sort of. And bolts and screws are pretty easy to make, but springs are a bitch. Springs must be annealed at very-specific temperatures, or they sag or break and generally don't last long.
- A basic hand-operated milling machine only costs a couple thousand dollars, and it would be useable for most of what you'd need. Making a decent barrel is a particularly-difficult task for the home-machinist, and so many people doing this in the US just buy a commercially-made barrel. This is simple to do as in the US the only government-controlled part is the receiver, any other part of a firearm you can buy or sell without any ID at all (in other countries this is not true--in the UK I believe the receiver and barrel are controlled). The machines for making barrels are big and very expensive and don't do anything but make barrels. And you need two: one drills the holes, and another cuts the rifling).
- Some guns were designed to require very little machining. Most of the books and plans I have seen floating around are for either the Mac-10/Cobray style pistols, or the old WWII-era Sten sub-machinegun. Neither of these requires much machining, it may be possible to assemble them with no actual machining--only using a hand file on them where necessary. The Mac-10/Cobray uses folded-sheet construction, while the Sten uses standard sizes of steel stock tubing. At gun shows it isn't unusual to find people selling "parts kits" for these guns (moreso the Mac-10/Cobray) which contain all the pieces except the receiver or a flat receiver, and buying such a kit is legal without any ID at all. Plenty of pictures and plans are floating free online, if you search. Brownell's has blown-up parts diagrams of both guns in their online parts catalog that you can look at.
- As for "modern" polymer construction like the Glock, you could probably find some workable material, but it might just be simpler to use metal for the whole thing.
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Isn't this essentially what any prototype engineer would do? How could it not be possible?

I was thinking that on modern automatics (like Glocks etc) the precision forging casting and machining requirements and tolerances are such that they could not be reliably manufactured in a home workshop without expensive, industrial level manufacturing equipment.

I saw a news special one time which showed a mideasterner making his own automatic weapon from scratch.
He must have had a pattern to go by because he poured his own castings in a forge in the ground.
Sorry I'm not a connisour of fine weapons so I don't know what he finally came up with but it was an automatic type weapon.Not a hand gun.

Please don't ask who when and all that other prove it stuff cause I just don't remember.

Back in my machinist days we chatted about this once in awhile. The consensus was that the barrel would be the only tricky part.

What do you think a machinist does all day? They make things typically with an accuracy of .001", often down to .0001" with little effort. In addition, 100K would outfit a home shop quite nicely with the basics: Bridgeport mill, lathe, supporting tools (saws and such) as well as precision tools (calipers, gage blocks, broaches and the like).

The weapon might not look exactly like a factory-made piece, but it would work quite fine. It wouldn't take a year either: it would probably take a week or two to do a proper job of it. Tool and die folks would have a better shot at it -- those guys are really good.